The present invention relates to a support attachment for use with a holding unit having two adjacent cavities for holding bottles and a method of using the support attachment. More particularly, the present invention relates to a durable support attachment that allows for manufacturing variabilities and firmly holds a wider number of manufactured bottles while the holding unit is moving.
Typically, in diagnostic investigation of a plurality of fluid samples, racks or bottle blocks are used to carry and hold several containers or bottles of samples. This is done not only for ease of movement of a plurality of containers as a single unit, but also for a transfer vehicle to carry the sample containing bottles through a diagnostic or analytic instrument.
These bottle holding units usually are rectangular in shape and have one or more cavities defining chambers in which bottles or containers of media, such as blood samples are carried. Glass containers or bottles are conventionally used for holding such samples.
Because the manufacturing tolerances of the glass bottles are larger than the tolerances allowed between an inserted bottle and the chamber, the chambers are manufactured with a built-in wiggle problem. Resilient packing material has been used so that the entire range of manufactured containers fit snugly within the chambers. For example, the interior of the chambers are lined with packing material, such as felt which resiliently presses against the side walls of a container inserted within the chamber. Such a device is described in co-pending U.S. patent application Ser. No. 07/351,476.
However, the use of resilient packing material, as described above, provides less than optimum support for bottles placed in a chamber. First, the initially obtained snug fit is not long lasting as the packing material itself, quickly wears away becoming thinner due to the inserting and removal of bottles. Further, the adhesive used to secure strips of the packing material to the interior of the chambers looses its stickiness and as a result, the packing material strips are pushed into the bottom well of the chambers. Since the bottles must remain still within the chambers to obtain accurate diagnostic or analytic readings of the samples, other materials and techniques have been tried to overcome these problems.
Instead of lining the interior of chambers, circular washers were installed on the top surface of each chamber of the bottle holding unit. The installed washers slightly overlapped the circumference of each chamber. Thus, bottles are first inserted into the narrower opening of the washer. The bottles are held within the chamber by the washer which hugs the sides or shoulders of the bottles. These washers were made from soft rubber first and then hard rubber, but the support obtained was less than satisfactory.
Soft rubber washers are resilient and easily receive various sizes of bottles. But the soft rubber wears away too fast and thus, loses its ability to hold a wide range of manufactured bottles firmly in place. The hard rubber washers are dependent on the specific size of the bottles and thus, only securely hold a portion of the number of manufactured bottles. While washers made from hard rubber retained their shape longer than the soft rubber, the elasticity of the hard rubber limits the number of bottles which the washer satisfactorily holds.
A heater block which holds a plurality of test tubes is described in U.S. Pat. No. 4,256,697 to Baldwin. Baldwin's heater block has a plurality of sockets or chambers, each of which is filled with suitable liquid having good heat transfer properties. The upper end of each chamber is enclosed by a resilient, flexible and elastic finger-like sleeve which can protrude downwardly into the chamber to be immersed in the liquid. Test tubes are inserted into the chambers through the sleeves which may be formed from any of a variety of suitably flexible, resilient and elastic materials such as an appropriate latex, plastic or silicone rubber material.
Applicants determined that the use of packing material or a strip of felt on the interior of each chamber within the block, as well as employing rubber washers or sleeves were less than optimum. According to Applicants' laboratory tests, bottles which were pulled out of and reinserted within chambers employing packing material or soft rubber needed to be replaced too often. Hard rubber washers gauged or ripped the identification labels of larger bottles thereby impeding the identification of the sample being tested and did not securely hold small bottles.